Zimbra Collaboration Two-Factor Authentication Bypass Vulnerability

A vulnerability exists in the EnableTwoFactorAuthRequest SOAP endpoint of Zimbra Collaboration (ZCS) versions 8.8.15 prior to 8.8.15 Patch 47, 9.0.0 prior to 9.0.0 Patch 46, 10.0.0 through 10.0.16 and 10.1.0 through 10.1.10. This vulnerability allows an attacker with valid user credentials to bypass Two-Factor Authentication (2FA) by modifying 2FA settings without a valid authentication token. The attacker can add a third-party authenticator app or email-based 2FA, gaining unauthorized access to accounts that require 2FA.

Impact

Exploitation of this vulnerability allows for unauthorized access to user accounts by bypassing Two-Factor Authentication requirements.

Remediation

Users can upgrade to ZCS 10.0.16, 10.1.10, 9.0.0 Patch 46 or 8.8.15 Patch 47, all of which include the necessary fix. Instructions for upgrading Zimbra Collaboration are available on the Zimbra website.